For Bad Boys Only: The Bad Boy Squad, a variety of private detective agency, is composed of King (Ekin Cheng Yi-kin), Queen (Kristy Yeung), and Jack (Louis Koo Tin-lok), whose primary source of business is the reuniting of clientèle with their first flames, and when the trio of young operatives returns to Hong Kong from an assignment in Thailand and the Squad's next three customers supply photographs of lost loves, the women in the pictures appear to be the same individual.